Statements

Painless supports all of Java’s control flow statements except the switch statement.

Conditional statements

If / Else

 if (doc[item].size() == 0) { // do something if "item" is missing } else if (doc[item].value == 'something') { // do something if "item" value is: something } else { // do something else }  

Loop statements

For

Painless also supports the for in syntax:

for (def item : list) { // do something }

for (item in list) { // do something }

While

while (ctx._source.item < condition) { // do something }

Do-While

do { // do something } while (ctx._source.item < condition)